DETERMINATION OF THE PROTONS ELIMINATED IN THE REGIOSELECTIVE DEPROTONATION OF SOME OPTICALLY-ACTIVE 3-KETO STEROIDS BY A CHIRAL LITHIUM AMIDE

被引：10

作者：

SOBUKAWA, M ^{[1
]}

KOGA, K ^{[1
]}

机构：

[1] UNIV TOKYO,FAC PHARMACEUT SCI,BUNKYO KU,TOKYO 113,JAPAN

来源：

TETRAHEDRON LETTERS | 1993年 / 34卷 / 32期

关键词：

D O I：

10.1016/S0040-4039(00)60687-1

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Mono-deuterated derivatives of optically active 3-keto steroids (4-2alpha-d, 4-2beta-d, 5-4alpha-d, 5-4beta-d, 6-2alpha-d, and 6-2beta-d) were treated with a chiral lithium amide ((S)- or (R)-2b) in the presence of excess trimethylsilyl chloride to give the corresponding diastereomeric DELTA2- and DELTA3-silyl enol ethers. It is concluded that the present deprotonation reaction occurs in chair conformation in 6, while in boat (skew-boat) conformation about the A-rings in 4 and 5.

引用

页码：5101 / 5104

页数：4

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